Household transport ownership and HIV viral suppression in rural Uganda: a cross- sectional, population-based study

Background Empirical data on transportation access and HIV treatment outcomes in sub-Saharan Africa are rare. We assessed the association between household transport ownership and HIV viral suppression in rural Uganda. Methods The study was conducted among people living with HIV aged 15–49 years using cross-sectional data from the Rakai Community Cohort Study (RCCS), collected from June 14, 2018, to November 6, 2020. Transport ownership was defined as household possession of a car, motorcycle, or bicycle. HIV viral suppression was defined as < 1000 HIV RNA copies/ml. Poisson regression with robust variance estimation identified unadjusted and adjusted prevalence ratios and 95% confidence intervals (CI) of HIV viral suppression by transport ownership. Results The study included 3,060 persons aged 15–49 living with HIV. Overall HIV viral suppression was 86.5% and was higher among women compared to men (89.3% versus 81.6%; adjusted prevalence ratio: 1.14, 95% CI: 1.10, 1.18). A total of 874 participants (28.6%) resided in households that owned at least one means of transport. HIV viral suppression was 79.8% among men and 88.2% among women from households without any means of transport, compared to 85.4% among men and 92.4% among women from households with at least one means of transport. Adjusted prevalence ratios of HIV viral suppression were 1.11 (95% CI: 1.04, 1.18) for males and 1.06 (95% CI: 1.03, 1.10) for females from households owning at least one means of transport compared with those from households with none. Conclusion There was increased HIV viral suppression among people living with HIV from households with transport means compared to those from households without transport means, suggesting transport may facilitate access to, and continued engagement with, HIV treatment services.


Background
Sub-Saharan Africa has the highest burden of HIV globally, 1 and achieving HIV viral suppression among people living with HIV reduces mortality and onward transmission. 2However, despite HIV treatment scale-up, many people living with HIV remain virally unsuppressed. 3For example, one study in south-central Uganda reported a viral suppression rate of 72.4% at the end of 2022; 4 another study conducted in south-western Uganda among adolescents found 81% viral suppression. 5This threatens to stall progress in the HIV response towards the UNAIDS 95-95-95 HIV treatment targets by 2030. 68][9] Additionally, travel costs and distance from households to HIV clinics have been identi ed as constraints to accessing HIV care. 10In Uganda, salient barriers to accessing healthcare include distance from households to clinics, perceived quality of care, and drug availability. 11qualitative study conducted with caregivers of children living with HIV in western Uganda showed that transport was a major barrier among participants exhibiting viremia. 12Costs incurred traveling to HIV clinics and di culty nding HIV clinics within reasonable travel distances from the home were shown to impede HIV care access individuals who were virologically unsuppressed in another study in rural Uganda. 13w studies have empirically explored the relationship between household transport ownership and clinical HIV outcomes.A mathematical model in Malawi singled out limited ownership of cars, motorcycles, and bicycles as a driver of HIV treatment disengagement. 14By comparison, a study among pregnant women in four African countries found no association between owning any means of transport and completion of the HIV prevention of mother to child transmission treatment cascade. 15Given the lack of empirical data on this relationship, we assessed the association between household transport ownership (car, motorcycle, or bicycle) and HIV viral suppression in rural Uganda, leveraging data from a large, population-based HIV surveillance cohort.

Methods
Study design and population.
This cross-sectional study used data from the Rakai Community Cohort Study (RCCS)-an open, prospective, population-based HIV surveillance cohort that enrolls consenting persons aged 15-49 years.The RCCS is implemented in 40 communities in rural south-central Uganda, which are broadly categorized as semi-urban trading centers, agrarian villages, and shing communities 16 with varying HIV burdens. 17A household census is conducted followed by survey interviews for eligible household members. 16This study was conducted using data from RCCS participants living with HIV, con rmed by laboratory results in survey round 19 (implemented from June 14, 2018 to November 6, 2020).
Transport ownership (car, motorcycle, or bicycle) was assessed through the household census, which asked the head of household about household possessions including motor vehicles and bicycles.Household transport ownership was enumerated from self-reported possession of at least one of the three means of transport.Blood samples were collected from all consenting RCCS participants, and viral load testing was completed for those with serologically con rmed HIV infection.HIV viral load testing was performed using Abbott m2000sp and m2000rt combined system.HIV viral suppression was de ned as < 1000 HIV RNA copies/ml. 18

Statistical analysis
The main outcome of interest was HIV viral suppression, measured dichotomously: suppressed or unsuppressed.The primary independent variable was household transport ownership, measured categorically (no ownership, bicycle, motorcycle, car, and at least one means of transport).Other variables considered included sex, age (with a spline at 40 years), community type (agrarian, trading, and shing), highest level of education attended (no formal education, primary, secondary, and tertiary), recent migration (in or within communities), socio-economic status (using Santelli et al.'s composite variable of enumerated household assets) 19 , distance (in kilometers) from household to the closest antiretroviral therapy (ART) dispensing facility (measured using a geodesic distance calculation from GPS coordinates of households and health facilities in the RCCS surveillance area, dichotomized to < 5 kilometers versus > = 5 kilometers based on the reasoning that there may be fewer transportation-related barriers to accessing health services in households closer to health facilities), and status as head of the household.
Poisson regression with robust variance estimation was used to identify unadjusted and adjusted prevalence ratios (adjPR) and 95% con dence intervals (CI).A priori, age and sex were considered potential confounders of the relationship between household transport ownership and viral suppression.Akaike's Information Criterion (lowest AIC) was used to select a parsimonious multivariable model adjusting for sex, age, community type, education level, distance from home to nearby health facility, and recent migration status.Analyses were further strati ed by sex, head of household status, and SES.Data analysis was conducted using Stata/BE 17.1 (StataCorp LLC, College Station, Texas).

Results
There were 3,332 individuals living with HIV, most of whom (64.0%) were female.Thirty participants (0.9%) had missing data on the primary exposure of interest (household transport ownership), and 242 participants were missing data on distance from home to nearest facility because they were missing global positioning system (GPS) coordinates for their homes; these were excluded from the primary analysis.Table 1 shows sociodemographic characteristics of the 3,060 participants living with HIV aged 15-49 years included in the analysis.A total of 874 participants (28.6%) resided in households that owned at least one means of transport.Most people with household transport lived in homes with a bicycle (20.8%, n = 637), and fewer with a motorcycle (12.2%, n = 372) or car (2.5%, n = 77).The mean age of all participants was 35.7 (standard deviation 7.5) years.The mean age was comparable between those whose households owned at least one means of transport and those that did not own any.Almost half of the participants (44.1%, n = 1,350/3,060) resided in households that were more than ve kilometers from the nearest health facility.The overall mean distance from households to the closest facility was 5.0 (standard deviation 3.1) kilometers (Supplemental Fig. 1).= 309/339) for those from households with motorcycles, and 90.9% (n = 70/77) for those from households with cars.Among males, all forms of household transport ownership were associated with higher levels of viral suppression; conversely, only bicycle and motorcycle ownership were associated with higher levels of viral suppression among females (Fig. 1).
Figure 2 illustrates the non-linear relationship between HIV viral suppression and age, strati ed by means of transport ownership and sex.Among males, viral suppression was consistently higher in individuals who resided in households with any transport ownership than in households without transport ownership.However, among females, differences in viral suppression by household transport ownership were only observed in older age groups and generally smaller than those observed in men.

Discussion
HIV viral suppression was approximately 8% higher among individuals from households that owned at least one means of transport compared to individuals from households that did not own any means of transport.The percentage increase of viral suppression, comparing any transport ownership to none, was larger among men than women (11% versus 6%).These ndings are consistent with the results of the modeling study in Malawi that found limited transport ownership as a barrier to HIV treatment coverage and viral suppression, and recommended increasing availability of bicycles in rural areas. 14usehold transport ownership may facilitate increased access and engagement with HIV services.Additionally, individuals in household with transportation access may have greater autonomy to seek HIV services from facilities with perceived better quality of care or where they are less likely to experience stigma, which have been identi ed as issues affecting access and utilization of health services in a systematic review of Ugandan health services. 11Billioux et al found that in the Rakai region, 57% of individuals living with HIV sought care from health facilities further away from their homes compared to their closest ART dispensing venue, 20 which could be an indicator of facility preference enabled by household transport ownership.
Our ndings suggest that there is need to explore how household transport ownership can be increased from the current relatively low 28.6% and whether such assets would impact HIV-related outcomes.Transport interventions -whether increasing transport ownership, increasing access to transportation resources, or expanding communitybased differentiated service delivery models -may contribute towards improved HIV viral suppression from current rates of ~ 75-95% targets by 2030. 3 In particular, more programmatic focus should be placed on men, who showed a stronger association between HIV viral suppression and household transport ownership.Prior data from this same cohort in south-central Uganda showed that limited HIV viral suppression among men was a major driver of continued HIV transmission in the region. 21Increasing viral load suppression -simply by providing bicyclesamong men could potentially attenuate gendered disparities in HIV viral suppression.
Strengths of this study included a large sample size from a well-established prospective HIV surveillance cohort.
Additionally, to our knowledge, this is the rst quantitative study of the association of household transport ownership and HIV viral suppression in sub-Saharan Africa.This study also had several limitations.For example, we assumed that any member of the household could use the means of transport that was available at home to travel to the facility for HIV services.Furthermore, we did not know the mechanism through which participants were receiving HIV care, e.g., some individuals may have received care through community-based differentiated service delivery models, which could have rendered them less reliant on transport.We also were unable to distinguish between speci c types of transport and their association with viral suppression.Finally, because of the crosssectional study design, we could not ascertain if changes in transport ownership were prospectively associated with improved HIV viral suppression.

Conclusions
There was a signi cant increase in HIV viral suppression among persons living with HIV who resided in households that owned a means of transport compared to those who did not.Increasing household transport ownership may contribute towards HIV viral suppression targets, particularly for men, and should be explored as an HIV care intervention.

Figures
Figures

Figure 1 HIV
Figure 1

Table 1
Socio-demographic characteristics of 3,060 participants by household transport ownership.

Table 2
presents associations between household transport ownership and HIV viral suppression-overall and by population strata.After adjusting for sex, age, level of education, distance from household to nearest health facility, and community type, the prevalence ratio of HIV viral suppression was signi cantly higher (adjPR: 1.08, 95% CI: 1.05, 1.11) among participants who resided in households with transport ownership compared to those without transport ownership.Results were similar irrespective of sex (men: adjPR: 1.11, 95% CI: 1.04, 1.18; women: adjPR:

Table 2
Association between HIV viral suppression and ownership of means of transport for 3,060 people living with HIV, strati ed by demographics and distance from home to facility.
*Adjusted for sex, age, community type, education level, distance from home to nearby health facility, and recent migration status *Adjusted for sex, age, community type, education level, distance from home to nearby health facility, and recent migration status